The present invention relates to an improved urinary catheter forming a continent urethral endoprosthesis intended for treating certain lesions of the urethra, the prostate or the urinary sphincters.
As is known, in the case of lesions of the above-mentioned kind, it is the practice to apply a urinary catheter, that is to say a flexible tube inserted into the bladder through the urethra in order to drain the urine.
Existing catheters cause discomfort to the patient mainly for two reasons, however: firstly, they protrude from the penis, and secondly they are not continent and must be plugged or to be connected to a urine collector tube. These reasons make them difficult to tolerate by the patient for a prolonged period or permanently.
A non-protruding urinary catheter, or urethral endoprosthesis by analogy with existing esophageal, biliary and like endoprostheses, constitutes an anticipated advance but one which does not exist at present in any practical form.
Indeed it has been difficult heretofore to devise and use a urethral endoprosthesis for the following reasons:
either the endoprosthesis is simply a tube open at both ends, devoid of any device or artificial sphincter to ensure continence; in which case it must be placed underneath the striated urinary sphincter if the patient is not to be made incontinent; the prosthesis is therefore difficult to position and moreover is of only limited usefulness for lesions located beneath the sphincter, to the exclusion of the much more frequent lesions located between the sphincter and the bladder, such as disorders of the prostate; PA0 or the prosthesis is rendered continent by means of an artificial sphincter, that is to say by a valve controlled by the patient.
However, such devices have been imagined and consist either of an electromechanically controlled valve, as described in French Pat. No. 73 40 939, or a valve controlled by the transfer of a fluid in a closed circuit, as described in French Pat. No. 83 14 607. These devices are complex in underlying principle and have found no practical application.